Spray device for dishwashing apparatus



1966 D. A. MEEKER ETAL 3,267,944

SPRAY DEVICE FOR DISHWASHING APPARATUS Filed Dec. 5, 1963 FIG -1 2Sheets-Sheet l INVENTORS DAVID A. MEEKER, THOMAS B. HECKMAN 8 GERALD B.FOX

ATTORNEYS Aug. 23, 1966 D. A. MEEKER ETAL 3,267,944

SPRAY DEVICE FOR DISHWASHING APPARATUS 2 SheetsSheet 23 Filed Dec. 5,1963 DAVID A.MEEKER, BY THOMAS B. HECKMAN 8 GERALD B. FOX

ATTORNEY United States Patent SPRAY DEVICE FOR DISHWASHING APPARATUSThis invention relates to an improved type of spray device fordishwashing machines, in particular, to an improved rotary spray deviceof the reaction type adapted to direct a plurality of streams ofcleansing liquid against articles to be cleansed.

Reaction type spray devices of this nature are generally constructed astwo or more spray arms extending from a hub which is in turn mounted torotate about an axis perpendicular, or substantially perpendicular, tothe spray arms. These arms in turn have usually included one or morespray openings or nozzles directed downwardly along their length andspaced outward from the hub, as well as a spray nozzle opening at theouter end of the arm which is directed downward and at an angle withrespect to the axis of rotation, such that liquid issuing therefromfunctions as a cleansing spray and partially as a reaction jet whichserves to rotate the device about its mounting.

An important feature of the present invention concerns an improvement insuch devices wherein the cleansing liquid is discharged along severaldifferent overlapping circular bands concentric with respect to the axisof rotation of the device, such that if looking along the axis ofrotation the spray pattern would be observed as several rings orconcentric circles of sprayed liquid which expand and overlap to providea concentrated but relatively evenly spread and uniform liquid spray,which is most effective in cleansing all portions of soiled articlescarried throughout the spray. On the other hand, according to theinvention the spray is substantially confined to within a predeterminedcircular pattern and thus relatively little of the cleansing liquidtends to be sprayed outwardly beyond the desired pattern, resulting in amore effective spraying and cleansing action. As a byproduct of thisimproved spray pattern the splashing of liquid to the outside of thechamber of the machine is reduced, and it is possible to attain a moreeffective splash guard arrangement whereby little of the spray liquid issplashed to the exterior of the machine.

The primary object of this invention, therefore, is to provide animproved rotary spray device for dishwashing machines in which thepattern of the sprayed liquid directed against articles to be cleansedis confined to an area which is essentially a direct projection of thediameter of the spray device along the axis of rotation of the device.

Another object of the invention is to provide such an improved rotaryspray device which is of simple and economical construction, and whichalso has a substantial useful life such that it requires littleattention for purposes of maintenance, and which when maintenance isrequired may easily be removed and disassembled for repair.

Another object of the invention is to provide such a rotary spray devicein which the sprayed liquid leaves the device in a plurality ofrelatively thin and wide sheets, with reference to the axis of rotation,and in which the direction of these sheet-like sprays can be adjusted toany desired angle with respect to the aXisof rotation to obtain adesired overlapping spray pattern and also to obtain the desired jetreaction to rotate the device.

Another object of the invention is to provide a novel ice spray devicefor dishwashing machines in which a stream of liquid is confinedinitially to flow through a fitting of circular diameter and in whichthe stream is redirected and guided to emerge as a relatively thin andwide sheetlike stream of liquid which is directed in a predeterminedrelation to the axis of rotation of the spray device.

Other objects and advantages of the invention will be apparent from thefollowing description, the accompanying drawings and the appendedclaims.

In the drawings:

FIG. 1 is a somewhat schematic view, broken away through the major partthereof, showing the overall arrangement of a typical dishwashingmachine in which the present invention is incorporated;

' FIG. 2 is a plan view, with one segment of the hub broken away andshown in section, of an improved rotary spray device according to theinvention;

FIG. 3 is an enlarged cross-sectional view taken on line 33 of FIG. 2,and showing in addition a portion of the mounting and supply pipe forthe rotary spray device;

FIG. 4 is an end view of one of the flow-directing scoop nozzles, asviewed from the perihpery of the spray device;

FIG. 5 is a detail view, on an enlarged section, showing the outletportion of one of the flow control fittings in the spray device;

FIG. 6 is a detail view showing the interior of one of the flowdirection scoop nozzle members; and

FIGS. 7, 8 and 9 and 10 are true sectional views (at the section lineonly) taken on the corresponding section lines indicated in FIG. 3, andillustrating the progressive change in cross-sectional dimension andconfiguration of one of the flow-directing scoop nozzles.

Referring to the drawings, which illustrate a preferred embodiment ofthe invention, FIG. 1 shows the overall construction of one form ofdishwashing machine in which the rotary spray device of the presentinvention can be incorporated. The machine includes an overall housing10 which is divided into a first cleaning chamber 12 over a tank 13, asecond cleansing chamber 14 over a tank 15, and a final rinse chamber 16which is located over one end of the tank 15.

The entrance to the first chamber 12 is provided by an opening cover bya flexible curtain 17, the chambers 12 and 14 are separated by aflexible curtain 18 as well as a splash deflector 19, the chambers 14and 16 are separated by a flexible curtain, a portion of which is shownat 20, and the exit of the machine from the final rinse chamber 16 isnormally covered or closed by a curtain 22. A conveyor structure,indicated generally at 25, is fitted to convey open mesh racks 26carrying the articles to be cleansed. This conveyormay be of the typeshown in US. Patent No. 2,073,521, or other types of conveyors may beused such as forms of continuous or so-called endless conveyors.

As is usual in machines of this type there are motor driven pumps (notshown) which withdraw the cleansing liquids from the tanks 13 and 15,respectively. The pump drawing from tank 13 is connected to supplycleansing liquid under pressure to a lower spray head 30 of conventionaldesign, and to an upper spray head 32 which may be a rotary spray deviceof the type provided by this invention. In similar fashion, the otherpump draws liquid from tank 15 and supplies it under pressure to theconventional lower spray head 33 and to the upper spray head 34 inchamber 14, and this spray head may also be a rotary spray device of theimproved type disclosed herein. The final rinse spray is preferably ahot fresh water spray supplied from a suitable source through pipe 35 tothe spray nozzles 37, and flow to this spray nozzle is controlled by themovable arm 38 sensing presence of Patented August 23, 1966 a rackbeneath the nozzle 37, and controlling the operation of a valve 39fitted in the line 35.

With reference to FIGS. 2 and 3, details of the improved rotary spraydevice provided by the invention include a hub member 40 provided with acentral sleeve 42 which is received over a shaft 44. This shaft extendsinto the end of a liquid supply pipe 45, and through the supply opening45 therein. The upper end of the shaft 44 is conventionally mounted in abearing for free rotation, and for this purpose of suitable sealedbearing (not shown) can be provided. The hub member 40 includes a forkconfiguration 47 adapted to fit with a cross pin 48 in the shaft 44, andthe hub member is secured to the shaft with the cross pin received inthe fork construction by a nut 50 threaded to the lower end of shaft4-4.

The top of the hub member is provided with a cylindrical inlet openingdefined by the cylindrical Wall or shoulder 52, and this shouldersurrounds the end of the supply pipe outlet 46 as shown in FIG. 3. Theliquid under pressure thus enters the central inlet passage or manifold54 of the hub member, and in turn passes through the several fluidpassages 55. These passages may be formed as short arms or tubes 56,preferably arranged in opposed pairs of different lengths as shown inFIG. 2. Thus, the liquid entering the hub member is divided into aplurality of streams flowing through the various passages 55.

At the end of each passage there is a flow control fitting 69 which hasan inlet section preferably of circular or essentially circularcross-section, indicated generally at 52. The outlet section 63 of thefitting, at its outlet end, is of approximately semi-circularconfiguration as seen by comparing FIGS. 3 and 5, and in between thereis formed in the bottom of each fitting a ramp or ilow direction portion65 which is flat, or substantially flat, and is inclined upwardly fromthe inlet section toward the outlet section of the fitting. Each fittingis received in a counter bore 67 in the end of the associated flowpassage tube 56,'and is held in place by a suitable clamping screw 68.Thus, each fitting can beadjusted to vary the relation of the rampportion 65 with respect to the axis of rotation of the hub member(defined by shaft 44) merely by turning the fitting to the desiredposition and tightening the associated clamping screw 68.

Fastened to each fitting, for example by being brazed to the extendingpart thereof around the outlet section 63, there is a scoop-like flowdirecting and controlling nozzle. These nozzles are indicated by thegeneral reference numeral 70, and may be of like construction. They arepreferably formed from thin and rather lightweight sheet metal, forexample stainless steel, although they can be formed by casting or inany other suitable manner. The inlet or flow-receiving portion of thesenozzles is indicated, particularly in FIGS. 3 and 6, at 71, and it willbe noted that the shape of the nozzle is approximately the same as theshape as the undercut portion 72 on the associated fitting 6t). Fartheroutward along the nozzle the side walls 73 diverge, as shown in FIGS. 7and 8, while the top wall 74 curves outward and downward as shown inFIG. 3. The progressive change in cross-sectional configuration can beseen by comparing FIGS. 7, 8, 9 and 10 with FIG. 3 of the correspondingsection lines thereof. Near the discharge end of the nozzle the sidewalls 73 are rather slight, and the nozzle is of rather wide and shallowcross-sectional configuration.

The flow of liquid under pressure entering the inlet section of fittingis redirected as the lower part of this flow impinges on the rampportion and is deflected upward. This causes the flow of discharge intothe scooplike nozzle member 76 and to follow its curved top wall 74configuration with the stream of liquid following appr oximately thepath shown by dotted lines in FIG. 3. Thus, the flow of liquid isredirected and shaped as it passes through the nozzle 79, such that itis expanded latportion of the scoop nozzle.

erally and tends to contract in a direction along the radius of thespray device. Thus, the exiting stream, in dicated generally at '75, isa relatively thin sheet-like flow of liquid which is expanding somewhatwidth-wise of the nozzle, as shown in FIG. 4.

As a result of the velocity of the exiting stream 75 of liquid, thisstream may tend to spread slightly outward away from the actualdirection of the discharge or exit However, this deviation of the streamis very slight, and the spray pattern is essentially a direct projectionof the circular paths followed by the nozzle members, as indicated inFIG. 2. In order to obtain the necessary rotary motion, one or more ofthe nozzles 7t) can be turned at .a slight angle with respect to thedirection of rotation, as shown in FIG. 4, and in FIG. 2 all of thenozzle members 70 are shown partially turned in this manner, although itwill be understood that it is not necessary that all of them should beso directed. The thin exiting stream from the turned nozzles will bespread somewhat in a band which extends along a plane intersecting thecircular path of the nozzle member, and thus it is possible also toobtain any desired overlapping of the spray from the individual nozzles,supplementary to the location of the various nozzles at dififerentradii, such that the resultant total spray pattern will be a series ofconcentric bands of liquid spray which overlap somewhat, but which aremaintained essentially within the circular projection of the path of thelargest diameter nozzle set.

This arrangement has been found most effective in attaining the desiredspeed of rotation, and direction of the liquid sprayed from the rotaryspray device, and simple adjustments can be made on machines in servicein order to obtain the desired result. For example, machines in which apredominance of the articles being washed are large and bulky, forexample cafeteria trays, or sectional trays such as those used in somemess halls by the armed services, may best be adjusted to obtain a moreeffective sluicing action of the stream, to assure cleansing of theinterior of the trays, particularly when such trays have soiledcompartments. Also, an improved spray pattern is achieved, in general,from the fact that essentially all of the liquid is directed onto thearticles to be cleansed, and very little of the liquid is sprayed intothe walls of the chamber, although of course some liquid will splashonto the walls after it has struck the articles being cleansed.

While the form of the apparatus herein described constitutes a preferredembodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes mayhe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. In a dishwashing machine having a housing defining a cleansingchamber and means for supporting articles to be cleansed in saidchamber, an improved rotary spray device comprising a hub member havinga plurality of radially extending liquid passages, means supporting thecenter of said hub member defining an axis of rotation of said hubmember extending vertically of said chamber, means forming inletpassages in said hub member spaced inward from the periphery of said hubmember and connected to said liquid passages, a nozzle member mounted toextend radially outward from said hub member at the radially outward endof each of said liquid passages, each of said nozzle members including acurved flow directing scoop having an inlet portion fitted to said hubmember and of approximately the same cross-sectional dimension as thecorresponding liquid passage, a discharge portion on each of said scoopsextending transversely to the associated said nozzle member to directall of the liquid flowing from the associated said nozzle member in adirection generally parallel to said axis of rotation and to confine theflow of discharged liquid essentially to Within a cylindrical path whichcoincides with the circular path of travel of the respective dischargeportions about said axis of rotation, and a curved guiding wallextending between said inlet portion and said discharge portion of eachsaid scoop, said guiding wall being curved through approximately 90 tochange the direction of liquid passing therethrough, said nozzle memberhaving a flow directing surface extending toward said guiding wall ofthe associated said scoop to direct substantially the entire flow ofliquid therethrough against the Wall surface of the associated saidscoop to cause the liquid to fiow along said curved wall of said scoopand to leave said discharge portion of said scoop in a relatively widestream.

2. In a dishwashing machine having a housing defining a cleansingchamber and means for supporting articles to be cleansed in said chamberand having a reaction type of rotary spray arm including a stationarysupply pipe in said housing terminating in a downwardly directed openingof circular configuration positioned above said supporting means and arotatable hub member supported for free rotation about said opening,said hub member including a plurality of separate fluid flow passagescommunicating with said supply opening and extending therefrom laterallyoutward of said hub member; the improvement comprising flow controllingand directing spray nozzles mounted on said hub member at the radiallyoutward ends of each of said flow passages, each of said nozzlesincluding a flow control fitting secured to said hub member and havingan inlet section of essentially circular cross-section and an outletsection of approximately semi-circular cross-section, a ramp portionformed in said fitting between said inlet and outlet portions thereofand extending upwardly from the bottom of said inlet portion toward saidoutlet portion to direct the liquid flow from the bottom of the inletportion of the fitting upward into the flow stream of liquid passingthrough the top of said fitting, and a flow-directing scoop carried oneach of said fittings, each said scoop including an inlet section ofinternal configuration corresponding at least at the top thereof to theconfiguration of said outlet portion of said fitting, each said scoophaving a further flow turning internal wall surface curved throughapproximately with respect to said fitting for changing the direction ofthe flow from said fitting from a generally horizontal direction to agenerally vertical direction, and said internal wall surfaces of saidscoops being formed to expand laterally with respect to said fittingproviding a relatively wide discharge end from which the stream ofliquid passing over said internal wall surface is discharged as a streamdirected downward in radially spaced relation from said hub member andexpanding in a direction generally transverse to the axis of rotation ofsaid hub member, said discharge portions of said scoops being arrangedat different radii with respect to the axis of rotation of said hubmember such that the fluid exits from the spray device as a plurality ofstreams at different radii and each of relatively thin dimensionradially of the spray device and of substantial width in thecircumferential direction about said hub member.

References Cited by the Examiner UNITED STATES PATENTS 270,664 6/ 1883Henderson et al 239-251 1,664,637 4/1928 Merseles et al. l 13472 X2,065,549 12/1936 Balensiefer 134l82 2,602,003 7/1952 Wellborn 134179 X2,983,452 5/1961 Lindbloom 239251 3,055,158 9/1962 Smith 239-251 CHARLESA. WILLMUTH, Primary Examiner.

EVERETT W. KIRBY, Examiner.

ROBERT L. BLEUTGE, Assistant Examiner.

1. IN A DISHWASHING MACHINE HAVING A HOUSING DEFINING A CLEANSINGCHAMBER AND MEANS FOR SUPPORTING ARTICLES TO BE CLEANSED IN SAIDCHAMBER, AN IMPROVED ROTARY SPRAY DEVICE COMPRISING A HUB MEMBER HAVINGA PLURALITY OF RADIALLY EXTENDING LIQUID PASSAGES, MEANS SUPPORTING THECENTER OF SAID HUB MEMBER DEFINING AN AXIS OF ROTATION OF SAID HUBMEMBER EXTENDING VERTICALLY OF SAID CHAMBER, MEANS FORMING INLETPASSAGES IN SAID HUB MEMBER SPACED INWARD FROM THE PERIPHERY OF SAID HUBMEMBER AND CONNECTED TO SAID LIQUID PASSAGES, A NOZZLE MEMBER MOUNTED TOEXTEND RADIALLY OUTWARD FROM SAID HUB MEMBER AT THE RADIALLY OUTWARD ENDOF EACH OF SAID LIQUID PASSAGES, EACH OF SAID NOZZLE MEMBERS INCLUDING ACURVED FLOW DIRECTING SCOOP HAVING AN INLET PORTION FITTED TO SAID HUBMEMBER AND OF APPROXIMATELY THE SAME CROSS-SECTIONAL DIMENSION AS THECORRESPONDING LIQUID PASSAGE, A DISCHARGE PORTION ON EACH OF SAID SCOOPSEXTENDING TRANSVERSELY TO THE ASSOCIATED SAID NOZZLE MEMBER TO DIRECTALL OF THE LIQUID FLOWING FROM THE ASSOCIATED SAID NOZZLE MEMBER IN ADIRECTION GENERALLY PARALLEL TO SAID AXIS OF ROTATION AND TO CONFINE THEFLOW OF DISCHARGED LIQUID ESSENTIALLY TO WITHIN A CYLINDRICAL PATH WHICHCOINCIDES WITH THE CIRCULAR PATH OF TRAVEL OF THE RESPECTIVE DISCHARGEPORTIONS ABOUT SAID AXIS OF ROTATION, AND A CURVED GUIDING WALLEXTENDING BETWEEN SAID INLET PORTION AND SAID DISCHARGE PORTION OF EACHSAID SCOOP, SAID GUIDING WALL BEING CURVED THROUGH APPROXIMATELY 90* TOCHANGE THE DIRECTION OF LIQUID PASSING THERETHROUGH, SAID NOZZLE MEMBERHAVING A FLOW DIRECTING SURFACE EXTENDING TOWARD SAID GUIDING WALL OFTHE ASSOCIATED SAID SCOOP TO DIRECT SUBSTANTIALLY THE ENTIRE FLOW OFLIQUID THERETHROUGH AGAINST THE WALL SURFACE OF THE ASSOCIATED SAIDSCOOP TO CAUSE THE LIQUID TO FLOW ALONG SAID CURVED WALL OF SAID SCOOPAND TO LEAVE SAID DISCHARGE PORTION OF SAID SCOOP IN A RELATIVELY WIDESTREAM.